How Many Solar Panels Do I Need in the UK
Jan 13th 2023
How Many Solar Panels Do I Need in the UK
Hello there!
Calculating how many solar panels you need for your house can be a confusing process. Most people don’t even know where to start. But it doesn’t have to be that way.
Determining the number of panels you need is simple if you follow the step-by-step process in this article.
●Usually, the first step to finding out how many solar panels you need is to understand your energy consumption habits.
●The second step is researching how many peak sunlight hours, also called peak sunlight hours, your region gets.
●The last step is performing the calculations by using the information gathered in the first and second steps.
After exploring how to calculate how many solar panels you need. We will answer some of your other questions, including the following:
● How many solar panels do I need for a 3 bedroom house in the UK?
● How many solar panels do you need for a four bedroom house?
● How many solar panels do I need to produce 2000 kWh per month
How to Calculate How Many Solar Panels You Need?
The process used to calculate how many solar panels you need can be broken down into three steps.
●Step 1 determines your daily electricity usage.
●Step 2 finds out how many peak sun hours you get in your area.
●Step 3 calculates how many panels you need to generate enough solar power to satisfy the daily energy usage.
Step 1: Determine Your Daily Energy Consumption
There are two methods you can use to find out how much electricity you use each day.
Method 1: By Using Previous Electricity Bills
You can find out your monthly electricity consumption by looking at your past electricity bills that have the amount of energy you used that month listed in Watt-hours.
For the best results, take an average of at least 3 previous monthly electricity bills. The result will better reflect your monthly energy usage.
Average Monthly Energy = [Month 1 (Wh) + Month 2 (Wh) + Month 3 (Wh)] / 3
Once you have the average monthly energy, divide it by 30 days to find your daily energy consumption. So suppose your monthly energy consumption on your bills is 30000Wh, here’s how to find your daily energy use.
Daily Energy Consumption(Wh) = Monthly Energy / 30 days
Daily Energy Consumption(Wh) = 30000Wh / 30 days
Daily Energy Consumption(Wh) = 1000Wh
Method 2: By Calculating Each Device’s Consumption
If you don’t have past electricity bills, you can also find your daily electricity use by making a table with the following items:
1.Your devices.
2.The number of repeated devices.
3.Each device’s wattage. If the device only has a voltage (V) and current (A) rating, you can find its wattage (W) by multiplying the voltage and current (Watts = Volts * Amps)
4.How long you normally use each device.
5.The daily energy used by each device.
6.The total energy used by all your devices each day.
Your table should look like the following sample table:
Total Daily Energy Used = Sum of Above Values = 1600+1440+1050+?+?+? = ?
You should add all the devices you want to power up with solar into the table. If you are having trouble finding a device’s wattage, check the device’s back, label, or manual.
Step 2: Determine Your Region’s Many Peak Sun Hours.
The peak sun hours, AKA peak sunlight hours, are roughly the number of hours when the sunlight intensity in your area will be around 1000 Watts per square metre (1000W/m2). So 1 peak sun hour can be written as 1000 Wh/m2 or 1 kWh/m2.
Different regions have different peak sun hours. For example, compared to other parts of the world, the UK gets dismally low peak sun hours that are usually between 2 to 3 peak sun hours.
Use the image below to find the number of peak sun hours in your area.
Data from Climatebiz
Step 3: Calculate How Many Panels You Need
Once you know your daily energy usage and peak sun hours, calculating how many solar panels you need is quite easy.
You only need to know 3 things to carry out the calculations:
1.Your daily energy usage, measured in Watt-hours (Wh).
2.The number of peak sun hours in your region.
3.The wattage of your panel measured in Watts (W)
Armed with the above information, you can use the formula below to determine the number of solar panels you need to satisfy your daily electricity usage.
Number of Panels = Daily Energy Usage / (Panel Wattage * Peak Sun Hours)
The table below uses the above formula to calculate the number of panels needed to generate 30000Wh using different panel wattages and peak sun hours.
Do note the UK gets low peak sun hours when compared to other parts of the world like Sub-Saharan Africa. So you will need more solar panels than someone in Sub-Saharan Africa to produce the same amount of power. Take the examples in the table below for 320W and 550W panels, where a UK citizen needs twice the number of panels as someone in a Sub-Saharan country like Zimbabwe.
Solar Power Calculator in the UK
Since we introduced our free online solar power calculator, it quickly became one of the most popular tools used by homeowners to calculate their daily electricity use.
The Renogy online solar calculator is a convenient and easier alternative to the pen and paper method outlined in Method 2 in Step 1 above.
The service is quite easy to use. All you need to do is:
1.Select a device in your house by clicking the options, using the search bar, or using the custom device option.
2.Enter the device’s wattage. The calculator has default wattages you can use if you don’t know your device’s wattage.
3.Enter the number of repeated devices. For example, if you have 3 TVs, show that in the respective textbox.
4.Enter the length of time you typically use each device.
After carrying out the above steps, you will find your daily electricity use listed in the bottom right corner of your screen, along with the list of your devices.
How Many Solar Panels Do I Need For a 3 Bedroom House in the UK?
According to Ofgem, a 3-bedroom house typically uses approximately 2900 kWh of electricity and 12 000 kWh of gas each year. This roughly translates to approximately 8000 Wh of daily electricity use and 33000 Wh of daily gas use.
To generate 100% of your electricity consumption using solar panels, check the following table with estimates of the number of solar panels you will need at each wattage.
We will still be using our previous formula, which says the number of panels is equal to your daily energy usage divided by the product of your panel wattage and peak sun hours.
Number of Panels = Daily Energy Usage / (Panel Wattage * Peak Sun Hours)
After our calculations, we see that depending on your chosen panel's wattage, you need anywhere between 8 and 40 solar panels to power a 3-bedroom house in the UK.
How Many Solar Panels Do You Need For a Four Bedroom House in the UK?
According to Ofgem, a 4-bedroom house in the UK will use around 12000 Wh of electricity each day.
We can use that daily 12000 Wh to determine the number of solar panels we need by using the formula:
Number of Panels = Daily Energy Usage / (Panel Wattage * Peak Sun Hours)
Also, the UK gets a range of peak sun hours that’s between 2 to 3 peak sun hours. So in the following table we will use 2.5 hours, which is the midpoint of our range of peak sun hours.
Using the table above, a 4-bedroom house in the UK needs between 9 and 48 solar panels depending on the wattage of your chosen panel.
How Many Solar Panels Do I Need For 2000 Kwh per Month
To determine how many solar panels you need to generate 2000 kWh or 2,000,000 Wh per month, you need to figure out your daily electricity use from a monthly consumption of 2000 kWh.
So how do you determine your daily electricity use?
You divide the monthly consumption of 2000 kWh by the number of days in a month.
Daily Energy (Wh) = Monthly Energy(Wh) / 30 days
Daily Energy (Wh) = 2000000 Wh / 30 days
Daily Energy (Wh) = 66667 Wh or 66.6 kWh
Once you've figured out your daily energy use, you can find the number of panels needed at each panel wattage using the formula below.
Number of Panels = Daily Energy / (Panel Wattage * Peak Sun Hours)
Number of 275W Panels = 66667Wh / (275W * 3 hours) = 81 (eighty one) 275W solar panels
So suppose you want to generate 2000 kWh each month using 275W solar panels. In that case, you would need approximately 81 (eighty one) 275W solar panels.
If you were to choose a higher-wattage panel than 275W, you would need less than eighty solar panels to generate the same 2000 kWh monthly. In contrast, if you opt for a lower-wattage panel you would need more than eighty solar panels.
Where can I buy the best solar panels in the UK?
With innovative minds and excellent technologies in the solar industry, Renogy pride itself on delivering high-quality and affordable products. Renogy offers a full range of solar products and accessories that are essential to complete an off grid solar power system, such as monocrystalline solar panels, 12V lithium batteries, and more. To Learn more about our products and up-to-date discounts, visit our homepage or contact us.
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Building An Off Grid Solar System In The U.K.
